Solved

Mail can not be delivered

Posted on 2009-03-30
10
1,008 Views
Last Modified: 2012-06-21
Hello there,

From time to time our client does not receive email from us.
We got an NDR with the following:
--------------
Your message did not reach some or all of the intended recipients.
The following recipient(s) cannot be reached:
....

The e-mail system was unable to deliver the message, but did not report a specific reason.  Check the address and try again.  If it still fails, contact your system administrator.

#2.0.0 smtp;221 Service closing transmission channel closing connection
------------------

I've checked http://mxtoolbox.com/blacklists.aspx it shows our SMTP's IP is not black listed.
We have Exchange 2003, the client's mx's port 25 respond with "220 SMTP Proxy Server Ready"

What is the most probable cause of the problem?

0
Comment
Question by:zc2
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
10 Comments
 
LVL 7

Expert Comment

by:december41991
ID: 24023006
This could not be a problem with you server most of the time. Its  that the recipient email address is not correct or those domain could not be resolved because MX record does not exist.
0
 
LVL 18

Author Comment

by:zc2
ID: 24023594
Thank you for the answer,

Email address IS correct. The recipients gets the email from us most of the time. But sometimes he does not and we got that NDR. The missed mx record is even less possible, because
basing on the "#2.0.0 smtp;221 Service closing transmission channel closing connection" string in the NDR I guess the connection to the recipient's mx was established, but then something went wrong.
Is there any kind of test I could apply to find out what is wrong?
0
 
LVL 7

Expert Comment

by:december41991
ID: 24023620
Is this happening to any domain only or randon to any domain.
0
Automating Your MSP Business

The road to profitability.
Delivering superior services is key to ensuring customer satisfaction and the consequent long-term relationships that enable MSPs to lock in predictable, recurring revenue. What's the best way to deliver superior service? One word: automation.

 
LVL 18

Author Comment

by:zc2
ID: 24024002
Apparently it happens only when mail is sent to that one recipient.
0
 
LVL 3

Expert Comment

by:cracksalsa
ID: 24024200
A helpful way to sometimes identify what is going on is to establish a connection from the command line. Identify the mx record of the mail server you are connecting to. open command prompt and telnet to the mx record on port 25. For example, if the mx record points mail.otherdomain.com then type at the cmd prompt:
telnet
open mail.otherdomain.com 25
helo yourdomainname.com
mail from: youremail@yourdomain.com
rcpt to: recipent@otherdomain.com
data
<type your data here.. ie: test msg>
end session by typing . on its own line.
Usually somewhere in there you will see it reject the connection but it will give you more data.
0
 
LVL 18

Author Comment

by:zc2
ID: 24024266
No there is nothing unusual.

220 SMTP Proxy Server Ready
HELO mysite.com
250 +OK SMTP server Ready
MAIL FROM:<myaddress@mysite.com>
250 +OK Sender OK
RCPT TO:<Recepient@otherdomain.com>
250 +OK Recipient OK
DATA
354 Start mail input, end with '<CR><LF>.<CR><LF>'
Subject: test again please respond
To: <Recepient@otherdomain.com>
From: <myaddress@mysite.com>
 
test. 
 
.
250 +OK message queued for delivery.

Open in new window

0
 
LVL 1

Accepted Solution

by:
pressonj earned 500 total points
ID: 24041373
Seems to me the issue is that your recipient is using an SMTP proxy server in front of the email server  (220 SMTP Proxy Server Ready)

Sometime proxy server may drop connection to the SMTP server due to time out etc.  
The SMTP message "#2.0.0 smtp;221 Service closing transmission channel closing connection" in the NDR is most likely from the SMTP proxy server that dropped the connection.





0
 
LVL 18

Author Comment

by:zc2
ID: 24044701
Is there what we could do, preferable on our side? Like rise the mail's importance level or something?
0
 
LVL 18

Author Closing Comment

by:zc2
ID: 31564517
The expert did not suggest anything to improve the situation and did not answered on my latest commnet.
I assume the answer he gave in his guessing is correct but that won't allow me to solve the problem.
0

Featured Post

Simplifying Server Workload Migrations

This use case outlines the migration challenges that organizations face and how the Acronis AnyData Engine supports physical-to-physical (P2P), physical-to-virtual (P2V), virtual to physical (V2P), and cross-virtual (V2V) migration scenarios to address these challenges.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This article will help to fix the below error for MS Exchange server 2010 I. Out Of office not working II. Certificate error "name on the security certificate is invalid or does not match the name of the site" III. Make Internal URLs and External…
A couple of months ago we ran into an issue that necessitated re-creating our Edge Subscriptions. However, when we attempted to execute the command: New-EdgeSubscription -filename C:\NewEdgeSub_01.xml we received an error indicating that the LDAP se…
In this video we show how to create an Address List in Exchange 2013. We show this process by using the Exchange Admin Center. Log into Exchange Admin Center.: First we need to log into the Exchange Admin Center. Navigate to the Organization >> Ad…
To show how to generate a certificate request in Exchange 2013. We show this process by using the Exchange Admin Center. Log into Exchange Admin Center.:  First we need to log into the Exchange Admin Center. Navigate to the Servers >> Certificates…
Suggested Courses
Course of the Month9 days, 22 hours left to enroll

623 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question